Basic Setup

Guntur District has 11 exchanges other than Guntur having more than 1000 lines capacity as well as SDCA Head quarters . Ten of these stations were provided with computers for SDE and DE, which were connected to main Database server at Guntur

These locations are connected to the server at Guntur via. One 64 KBps PCM channel. AT all locations, this channel is derived from 2MBPS stream by placing 6 channel 64K Codirectional/Data cards at both ends of the PCM stream.

This 64K data is fed to the Interface converter(SPD-703)(G.703 to V.35) at remote end which in turn gives output to WAN port of the branch router and from this it goes to the hub via LAN/Ethernet port i.e. Local area network.

At central end all these 10 locations 64K Channels terminate on 10 circuits of Multiplexer directly from PCM.

Where as the Mangalagiri location is connected using one 64K PCM Channel that is derived from 2MBPS stream using Drop/Insert equipment at both remote and central site.

At Mangalagiri 2MBPS stream is directly fed to the Drop/Insert equipment and from here it drops one 64K PCM channel which is fed to the WAN port of the branch router and remaining 2MBPS i.e. 29 Channels is fed to the Exchange. From branch router the output is fed to hub via LAN/Ethernet port.

At central end for the 2MBPS stream coming from Mangalagiri is fed to Drop/Insert equipment, from there output is fed to SPD-703(Converter) whose output is terminated on one circuit on Multiplexer.

In the case of Guntur there are 8 locations, and these are connected on two cable pairs(copper wire) which supports up to 64K (V.35) Modem. The output is fed to the WAN port of branch router which in turn fed to hub via LAN/Ethernet port i.e. LAN.

At central end all these are terminated to 8 circuits of Multiplexer through 64K (G.703) Modems.

All the circuits from all the above locations finally terminates on 4 Circuit data cards of the Multiplexer which has total 20 data circuits. This Multiplexer multiplexes the data from all these locations into a 2MBps stream (E1) and this is fed to the E1 port of the central router which is at central location. The output of the Central router is fed to the central Hub/LAN through LAN/Ethernet port which connects central router, Multi switch ,Terminal servers Main database servers as well as Network Management server. All these will be on the local LAN at central site thus providing access of the central Database to all the nodes of SSA which are at the above mentioned sites.

Regarding some locations or nodes which are far away from exchange premises i.e. unable to connect with network cabling are connected to the main server through dialup lines (DEL’s) using dialup modems at both ends. All these Modems at Central location were connected to an 8 port Async Terminal Server. The output of the Terminal server is fed to Central Hub via LAN/Ethernet port . If any such node wants to access the server at central location he has to dial a particular number and the dialup modem at central location receives the call and through the port of terminal server it enters the local LAN of central site.

All the Networking components which supports SNMP i.e. Routers, Manageable hubs, switches etc can be managed from the Central location using Network Management Software which was loaded in Network Management server. We can also monitor the status of all the components, traffic in various route’s/locations using a layout diagram with different colours for different status for each device.

Any user/officer at any location can access the database with his proper authentication username & password such that he may query , update, enter ,process the data according to the privileges granted by the database administrator.

Regarding the security of dialup lines, the security will be at both modem level which has Dial backup facility as well as at database level.